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I want to hook up my bedroom TV and digital cable box. Question: can I run the coax cable through a heat duck from bedroom to basement? There really isn't another way to do it without running into a mess. Would the heat from furnace heat the coax too much? Is there any harm in doing this?
 

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One thing to keep in mind is that if you open up the warm air pipe to insert a cable; you will lose some heat. The question is; how much will that cost you in the long run?

I use the cold air returns for most of my cable runs.

You also might want to re-think your title for this thread; if you want to get more opinions. A title like "Question" is very vague; almost every thread could use that as the title.
 

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Trickman said:
I want to hook up my bedroom TV and digital cable box. Question: can I run the coax cable through a heat duck from bedroom to basement? There really isn't another way to do it without running into a mess. Would the heat from furnace heat the coax too much? Is there any harm in doing this?

Keep in mind that if you sell your house you should disclose this or take the wire out because it is against the electrical code. Some places will exept FT6 (plenum
rated wire) and some won't.
 

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Coax strung in HVAC systems is the typical way of retrofitting old buildings so you should be fine. I was part of a team that strung old high schools that way in the early 1970s. After crawling through all that old venting all day I would get home covered in decades-old dust... :mad: yuck...

For home use plenum cable was already mentioned in this thread if your heating system runs especially hot or humid, but you will probably be okay with standard coax. Either way make sure its rated RG6. If its an apartment building or a large installation you want to avoid heavy line losses by investing in RG11 as the main carrier before splitting and/or amplifying with RG6.

cheers,
stampeder
 

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coax cables through heating ducts

I heard that you shouldn't run coax through heating ducts.
In my sisters house there are a couple cables that are routed this way.
I'm thinking about rerouting them through the cold air return.
Anybody have any comments on this?
 

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I have run cables through the cold air return in my old house. At the spot where they came out of the cold air return column in the basement I used furnace tape (the metal stuff) to seal the gap created by the cable.
 

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Hi,

The installer from the cable company in fact wanted to use the ducts as his first preference when he came in to wire a point to the 2nd floor from the basement. So I think it should be fine.
 

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Did he want to run them through the heat duct, or through the cold air return?
Anyways I ran them through the cold air return.
Just wired up the three bedrooms upsatairs with just phone and cable.
 

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Through the heat duct. Eventually, he couldn't do it that way because of the length of the run and a bend just above the basement that he couldn't resolve. What he did was to drill a hole in the wall, run the cable outside the house and drilled another hole to bring it back in. It looks ugly but it's in the back - I noticed my neighbour has a similar cable on his wall in the back too.
 

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Absolutely not!!!

The electrical code very specifically prohibits running cable inside hot air ducts. They can cross perpendicularly through a hot air duct if necessary, for example when a joist space is used to channel hot air. The point is not to have anything flammable in the ducts that would push smoke and flame throughout the house.

Use the cold air return. And make sure the cable is fire rated. I've noticed Cat5e being sold as plenum and also riser. They aren't the same thing.
 

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Yes you can.

Is it legal or to code, probably not, even plenum rated cable or high fire rated cable do not meet most codes and for the price of FT4 or FT6 rated cable you could hire someone to run regular RG6 properly and to code.

Is it a risk? Yes it is.

Most of the answers here would probably say you do not need to ground your dish & each coax cable before it enters the residence. Same answers, is it legal to install without grounding properly? No!!! Is it done (by most so called cable experts)? Absolutely and it is quite likely illegal in most Provinces, Territories and US States! Is it a high risk? Who knows...some people have been hit by lightning numerous times and lived.

Could you be denied insurance payments for a fire that has roots in the non-code wiring? Absolutely!

One last point....don't forget you have tyhe cable in your duct work when you decide to have someone use the robotic style of duct cleaning equipment!!!! Kinda does a job on cables lying in your duct work!!!!! LOL
 

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if my memory is correct your house is concidered a combustable(wood) building so a ft1 rating is all that is required- basically anything goes as long as it is csa rated. Noncombustable(concrete) building require ft4 and ft6 cables to be installed for flamespread and smoke production. This is the ontario building code.
Now plenum cable does not work any better or worse in a hot location. heat will cause the resistance to increase, so this is bad. Also the cables have a csa temputerature rating - typical is around 90 degrees C. The typical output temp of a gas furnace is 110 to 120 degrees C and a heat pump is around 95 degrees. So if you put cables that are not rated for the heat your installing them in , your asking for trouble.
Installing the cables in the return should be fine as long as it is not to many and doesnt cause reduction in air flow. Reducing air flow will cause your furnace to not work as well and even cause it to over heat and trip out the thermo protection built into the furnace.
I would suggest you find a better way to do this. Take a nice piece of pvc conduit and run it up the outside of your house - create a raceway from your basement to your attic.
 

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Actually, no. There is substantial confusion on this, since you ARE permitted to run wiring through cold air return joist spaces. As well, the CEC addresses the matter only peripherally. It specifies that all cable and applications thereof must be listed in Table 19 (2015). CEC is pretty much in line with US codes as well, and both countries derive much of their electrical regulations from national building and fire codes. Running wiring (not only power but also communications cables) in hot air ducts is simply not listed, period. ie. not permitted. Wiring in cold air return ducts and plenum ceilings on the other hand IS permitted (and is so mentioned in several locations in the code). Even there, the wiring must meet certain flame spread ratings. Several types of communication cable are specifically permitted in air return plenums, including CATV coax type "CMG" popular with some cable TV companies. (In a properly rated coax, the marking is printed right on it at intervals along the jacket.) Multiple issues such as degradation of approved cable temperature limits, impact on FT rating, and loss of HVAC supply air flow, are raised by running wiring of any type in a hot air supply duct. These issues are deemed less significant in return air paths. As for FT rating (eg FT6), it does not so much guarantee absence of toxic combustion products (eg. cyanide). Rather, it guarantees that the cable itself will not readily feed an existing fire. -- licensed electrician
 

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Well put. In addition, modern heating system practices would make it nearly impossible not to use cold air plenums for running cables. Ceiling spaces in offices and spaces between joists in residences are often used for both return air and cabling. Regulations could be revised to eliminate such practices but it would increase costs and retrofitting existing buildings would be prohibitively expensive.
 
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